C. 1349. Charlie and his friends like playing poker dice. Charlie decided to play a prank on his friends, and on one of the five dice he eliminated the central dots of the faces with 3 and 5 dots. Now that die shows one 1, two 2's, two 4's and one 6. The next time they played, no one noticed the trick.
If one rolls the five dice prepared in this way, what is the probability that at least four identical numbers will appear on top?
This problem is for grade 11 - 12 students only.
Deadline expired on 11 April 2016.